In order to give full play to the effect of the bearing in the machine, in addition to selecting the type and type th...
In order to give full play to the effect of the bearing in the machine, in addition to selecting the type and type that matches the system, the correct combination structure planning must be stopped. This needle roller bearing is also the same. What are the contents of the needle roller bearing assembly plan? The combined structure planning of the needle roller bearing includes the shaft support end structure; the cooperation of the bearing and related parts.
The lubrication and sealing of the bearing; and the movement of the rigidity of the bearing system, etc., these are the guidelines that need to be reached, otherwise the needle roller bearing will not be able to operate normally. In addition, there is also the fixing method of the needle roller bearing. If the two ends are fixed, each bearing bears the bearing force in one direction respectively, which allows a small amount of heat shrinkage during the shaft operation.
At the time of the official equipment of needle roller bearings, there should be an axial space of 0.25mm-0.4mm, which can be carefully arranged through gaskets or screws, but this fixing method will restrict the bidirectional movement of needle roller bearings, so it is generally suitable for use On some shafts with little change in operating temperature, it is necessary to consider thermal elongation and leave a compensation space between the bearing cover and the outer end surface.
Assuming that only one end of the needle roller bearing is fixed in both directions, and the other end is kept in the swimming state, it can ensure that the bearing can move freely when it is elastic. The fixed end of the needle roller bearing is mainly the two-way axial force borne by the single bearing or the bearing group. In order to avoid loosening and falling, the internal range of the floating bearing and the axis are fixed.
Explain in detail the advantages of needle roller bearings
The advantages of needle roller bearings are introduced in needle roller bearings, which are composed of two main rollers installed in different directions, side rollers and shaft heads to reduce space and reduce manufacturing costs. The bearing capacity of radial and axial direction devices is relatively large, and the components can be exchanged. Among them, the adjustable combined roller bearing can be adjusted by adjusting the eccentric outer hexagon or eccentric valve to adjust the position of the core shaft to achieve the purpose of adjusting the axial size of the side roller.
Needle roller bearings are mainly used in: shelves, forklifts, stackers, metallurgical industry, container front forks, cranes and other large cranes and material lifting equipment. The advantages of needle roller bearings: the friction coefficient of needle roller bearings is small, so the friction resistance is low. The starting friction torque is small, and the power consumption is low; the external dimensions have been internationally standardized, serialized and generalized, suitable for mass consumption, good interchangeability, and easy to install, disassemble and maintain.
Needle roller bearings have small internal clearances and high machining accuracy. The rigidity of the bearings can be improved by applying preload, which is very important for precision machinery; needle roller bearings have high transmission efficiency, less heat generation, convenient lubrication and maintenance, and lubricants saving; load , The speed and working temperature have a wide compliance range, and the few qualitative changes in working conditions have little effect on the performance of the bearing.
Ordinary, most types of bearings can bear radial and axial loads at the same time, which can simplify the structure. Compared with sliding bearings, needle roller bearings have their own advantages and disadvantages, and each occupies a certain applicable place. Therefore, the two cannot be completely replaced. However, due to the outstanding advantages of needle roller bearings, needle roller bearings have now become the main support type for machinery, and their applications are becoming more and more common.